Direct answer
CR2032 and CR2025 share 20 mm diameter, 3 V nominal voltage and lithium manganese-dioxide chemistry. The decisive difference is height: 3.2 versus 2.5 mm. The 0.7 mm gap can change contact pressure and available internal volume.
Both are 20 mm in diameter; heights are 3.2 mm and 2.5 mm. The physical envelopes differ (20 × 3.2 mm versus 20 × 2.5 mm). Do not force, stack or infer equivalence from a shared diameter or code pattern.
Do not infer acceptability from fit alone. The device maker’s complete code and current instructions remain authoritative.